M1 macrophages predominantly secrete pro-inflammatory factors such as tumor necrosis factor alpha (TNF-α), IL-6, and IL-1β (Gordon, 2003,2007), all of which have been shown to be expressed at elevated levels in the PF, serum, and ectopic lesions of patients with EMs (Bergqvist et al., 2001; Richter et al., 2005; Cho et al., 2007; Wang F. et al., 2018; Wang X. M. et al., 2018; Jaeger-Lansky et al., 2018; Volpato et al., 2018). This evidence concerns the gene TNF and eosinophilia-myalgia syndrome.